Medicinal plants have been extensively used to treat a variety of infectious and non-infectious ailments. As the number of viral infections and in particular resistant viral strains increasing, current remedies need to be upgraded and brought into line with the discovery of new antiviral agents to combat persistent viral infections Nature has already conferred on us a wide variety of antiviral remedies in the form of herbs, they are characterized with a broad antiviral spectrum. Several plants could offer a rich reserve for drug discovery of infectious diseases, particularly in an era when the latest separation methods are available on one hand, and the human population is dared by a number of emerging infectious diseases on the other hand. Of importance, a variety of medicinal plants have shown promise effect to treat a number of viral infections, and some of them have broad-spectrum antiviral activity. Among several other ailments, viral infections, particularly infections connected with human immunodeficiency virus type 1 (HIV-1) and 2 (HIV-2), influenza virus, hepatitis B virus, viruses causing respiratory infections, severe acute respiratory syndrome (SARS) virus and newly emerging infectious viruses have challenged mankind survival. Viral infections affect about three to five million patients every year. While frequently used antivirals often show limited effectiveness and sometimes may have serious adverse effects. This article describes potential antiviral properties of medicinal plants against a diverse group of viruses, and suggests screening the potential of plants possessing broad-spectrum antiviral effects against emerging viral infections.